Artificial limb



J. F. RUWLEY. AR'HFH'HM, LIME. APPLICATION mm JULY m. 1920.

MFR

Patented Feb. 15, 1921.

UNITED STATES PATENT OFFICE.

M sums r. now'nnr. o1- cnrcaco, ILLINOIS.

ARTIFICIAL L113.

and State of Illinois, have invented certain in Artificial new and useful Improvements is a specifica- Limbs, of which the following tion.

This invention relates to means for producing the desired action of an artificial limb, and more articularly to controlling devices for ben ing and straightening a leg. The present invention is of the same general character as that disclosed in applicants copending application Seriah No. 394,062, filed July 6, 1920, but includesl certain develo ments of the structure disc bsed in said app ication for patent. w

An ob]ect of the invention is to provide a le controlling mechanism which is operab e by movement of the wearer to alternately flex and straighten the le and which will operate correctly during or i ry w lkiniwithout special'attention of e-dveq rer.

further object rovide' a construction which is operative ue to a single extension of the body of the wearer of the limb to first then straighten it with the end in view of attaining a correct action for walking by the simplest means.

A further object of the invention.is to Brovide a leg straightening device operable y an extension 0 the b0 y of the wearer and opposed by a resilient leg flexing device, said leg flexing device being arrange to move toward an ineii'ective position as the legrbends.

hese objects are amomplished by the structure shown in the accompanying'drawing in whichigure 1 is a sectional view of an artificial leg constructed according to this invention. r

Fig. 2 is a plan view of the controlling mechanism for the lower leg section.

Fig. 3 is a front view of the entire leg with its suspender.

The aim of this invention is to enable the user of an artificial leg to walk correctly without particular attention to the control of the leg and to enable him to control its action as desired both in bending and straightening the eg. To this end means is provided whereby upon a forward and rearward movement of the thigh to which Specification of Letters rum.

Application fled July 1c,

of the invention is to' bend the leg and Patented Feb. 15, 1921.

1020. V semi x scam.

the leg is fitted, the leg ens and bends to the desired extent. means com rises the suspender support for the leg an its particular connections with the'lower leg section. When the weight of the wearer is on the leg it is maintained in its strai htened position, but as the weight is tran erred to the remaining leg the straight one swung toward, its extreme forward position it is again straightened. Both the bending and straightening of the leg may be due to change in tension of the suspender occurrin during the act of walking. A tensioning o the suspender first acts upon one side and then the other of the pivotal connection between the leg sections.

The particular construction by which the invention is carried into efiect comprises the usual design of le sections ivotally connected as by a knee leg section being provided with an arm or lever by means of which through suspenders this section of the leg may be swung to straightened relation with the thigh section. The outer end of the lever has a .roller connection with loops of the sup orting suspender. inwardly of the pivots. connection between the two leg sections the suspender loop also has a roller connection with a leg bending strap or elastic web. By this construction an extension of the body of the wearer of the limb causes the Suspender loo 5 to first draw upwardl on the leg flexing W5), and after the leg is ent to the desired degree for alking, the continued tensioning of the Suspender results in a reverse action. that is, the loop operates on the forward end of the le straightening lever. The leg straighten ng lever forms a bearing for the and this alternately strai htis so formed that the carrie at the upper end of the strap will be guided toward the pivotal connection be tween the leg sections as the leg is bent, and in this manner the resistance of the elastic web is reduced as efiort is applied for straightening the leg.

The invention as illustrated in the drawings may be practised by means of a leg construction consisting of a thigh portion 1 and a lower leg portion 2 pivotally connected by aknee bolt 3. Attached to the lower 1 ,section is an arm or lever 4 which may be ournaled on the knee bolt and carries at its upper forwardly extending end first bends slightly. but as it is his olt, and t e lower a double grooved pulley 5 around which ass the loops 6 of t e supporting suspender l Reai-wardly of the knee bolt 3 the suspendcr loops pass around pulleys 8. The rec tangularly bent rod 9 upon which the pulley 8 is journaled is attached to the upper end of an elastic web 10. This web is secured at its lower end to the lower leg'section considerably below and to the rear of knee bolt 3. Apad 11 is carried at the upper end of web 10 for hearing on the curved surface 12 of lever 4. 7

With the construction described, an upward drawing of the loop 6 by a body motion of the wearer results in tensioning the web 10, but as the knee bends under this action the pad '11 rides upwardly on the curved surface 12 of the lever 4 toward the knee bolt, in which osition the web 10 becomes less effective or resisting continned upward motion of loops 6. Such continued motion becomes effective on the forward end of lever 4 and returns the lower leg section in straightened relation with the thigh section. In this manner a single extension of the body of the wearer may result in both bending and straightening the leg. This volitional action is particularly convenient for walking through heavy snow or up Stairways or wherever walking is more diflicult than normal. In normal walking over a level surface the leg has some pendulum action. When it supports a weight it is of course maintained straight a ainst the resistance of elastic web 10, but w ten it is relieved of its load the web assists in flexing the leg upon the forward motion of the thigh, but the suspenders tension slightly during this motion and with the forwardly swinging weight of the lower leg section overcome the resistance of web 10 so that the leg is again straightened before the foot reaches t e ground.

Although but one specific embodiment of this invention has been herein shown and 4!.

described, it will be understood that numerous details of the construction shown may be altered or omitted without dcqmrting from the spirit of this invention as defined by the following claims.

I claim:

1. An artificial limb, comprising two pivotally connected sections, means for changing the angular relation of said sections, a resilient element oiposed to said means and slidably connected therewith to move toward ineffective position during operation of said means.

2. An artificial limb. comprising two pivotally connected sections, a lever to straighten the leg, a resilient element 0pposed to said lever and slideblv connected therewith to move toward ine ective position during OJQIiItlOIl of said lever.

3. An arti cial limb, comprising two pivotally connected sections, means to straighten the leg, a resilient element for opposing said means, said means being arranged to shift said resilient element into inoperative position. Y

4. An artificial lini'b, comprising two pivotally connected sections, one means for flexing and one means for straightening the limb. the flexin means having an element which is move is to render the flexing means ineffective for resisting the straightening means after a predetermined action.

5. An artificial limb, comprising two ivoted connected sections, one means for texing and one for straightening the limb, the llexin means having an element which is move le to a position to render the flexing means less effective for resisting the straightening means after a predetermined action.

Signed at Chicago this 7th day of July,

JAMES F. ROWLEY. 

